Permanent magnet synchronous motors (PMSMs) are widely used in industrial drives, but common-mode voltage (CMV)—an unwanted electrical phenomenon in inverter-based motor systems—continues to degrade performance and reliability. CMV causes electromagnetic interference, leakage currents that damage motor bearings, and accelerated wear of electrical insulation, ultimately shortening equipment lifespan.
Researchers have proposed a refined model predictive control (MPC) strategy that specifically targets CMV reduction without compromising motor performance. The method incorporates a dedicated weighting factor into the control algorithm's cost function, explicitly penalizing CMV generation during each control cycle. This modification allows the controller to balance multiple objectives: precise current and torque regulation alongside CMV suppression.
The innovation uses a simplified two-vector approach, applying two nonzero switching vectors per sampling instant rather than exhaustively evaluating all possible inverter states. This reduces computational demand while maintaining control quality—a practical advantage for real-time digital implementations on embedded hardware.
Validation through both simulation and hardware testing demonstrates significant improvements. The experimental results show 40% reduction in CMV magnitude and 25.5% reduction in stator current total harmonic distortion (THD) compared to conventional MPC methods. Lower THD means cleaner power delivery to the motor, reducing acoustic noise and heat generation.
The approach addresses a fundamental engineering challenge in power electronics: minimizing parasitic effects that accumulate in high-speed switching systems. By explicitly controlling CMV, engineers can extend motor lifetime, reduce bearing failures, and minimize electromagnetic compatibility issues—particularly important in sensitive industrial environments or aerospace applications. The simplified computational structure also makes the method viable for cost-sensitive applications where advanced hardware may be unavailable.
